Present day monitoring devices are typically designed specifically for different care areas inside or outside of a hospital. In the case of a trauma patient, the monitoring typically begins at the site of the accident. Ambulances carry transport monitors, which have been designed to be rugged for use in mobile ground and air vehicles. The patient is transported to the hospital and may initially be held in an emergency room (ER) for evaluation of the severity of the accident or illness. This usually requires disconnecting the patient from the ambulance monitor and reconnecting the patient to the ER monitor. Monitors for this area of the hospital often have a wireless connection to a central station monitor and information network allowing the monitor and patient to be mobile so they can be deployed, viewed, and controlled where needed in the ER. If a patient is critically ill the patient is typically taken to an operating room (OR) or to an Intensive Care Unit (ICU), and again disconnected from the ER monitor and reconnected to the OR or ICU monitor.
A patient is usually moved from an OR to a recovery area and then to an ICU, or from an ICU to a less-acute “step-down” area or “ward”, and again may need to be physically disconnected and reconnected from the OR monitor to a transport monitor or to an ICU or step-down monitor. Healthier patients may be outfitted with wearable “Telemetry” devices that are semi-mobile or mobile to allow a patient to leave the bedside and ambulate within a care unit or hospital. Fully ambulatory patients may be permitted exercise by walking within a specific area designated by a clinician. After further improvement in physiological status a patient may be no longer need to be continuously monitored but has vital signs periodically spot-checked and is eventually given a final complete evaluation before discharge.
It is desirable that a portable patient monitoring device with fixed and mobile modes of operation is used to support the different patient treatment stages in order to continuously monitor a patient even during those times when a patient is in transit, e.g., between patient room, examining room, operating room, etc. It is further desirable that a portable patient monitoring device is able to identify patient location or at least a location of a current docking station to which it is attached in a fixed mode of operation. Known systems used to determine location information of a portable device attached to a docking station use complex docking station technology and are consequently costly, lower in reliability and are typically also power hungry. These factors are particularly burdensome when large quantities of docking stations are employed in a hospital, for example. A system according to invention principles addresses this problem and associated problems.